一种改进的无线ATM多址接入协议—MAS++协议

【作者】 蒋觉先；

【导师】 杨邦荣；

【作者基本信息】 中南大学 ， 通信与信息系统， 2005， 硕士

【摘要】 现代通信正朝着两个不同的方向飞速发展,一个是面向全球范围日益增长的宽带通信;另一个是基于蜂窝小区结构的无线通信。因此带宽和移动通信是当前电信业中两个主要推动力。目前,宽带通信和移动通信还是沿着各自的方向发展着,但便携式计算机和移动通信的重要性日益显示出来,这也促使着将无线接入技术引入ATM网,以实现无线通信网和ATM网的结合,因此就出现了无线ATM技术。而无线ATM作为ATM技术的延伸,应具有QoS的保证,但无线信道资源有限,且具有时变性、差错率高等特点,因此如何保证QoS是人们关注的重点问题。本文就是从这里入手,开始先对目前主要的多址接入协议的帧结构、协议的竞争机制、信道的分配机制进行分析,了解它们的运行机制,针对其中的一个协议的不足,提出了改善的想法,在这样的基础上结合其他协议的优势,设计出自己的协议,对帧的结构和竞争机制有大胆的改变。然后通过先进的网络仿真软件OPNET建立这个协议的三层模型,从理论上先对业务源模型进行讨论,在实现中只针对语音这一类业务进行参数配置,实现最后的仿真。通过两次给出不同数目的业务源模型,来比较仿真情况,分析仿真结果,说明该协议的一些优缺点。在本文的最后针对无线ATM技术在多址接入方面提出了一些看法,同时对该技术的前景有一个展望。更多还原

【Abstract】 Modern communication is developing at full speed towards two different directions, One is broadband communication increased in global range, the other is wireless communication on the basis of the structure of the cell phone. So bandwidth and mobile communication are the two important motive force in the present telecommunication. Now the broadband and mobile communication are growing along one’s own ways. But the importance of them shows day by day, it makes wireless technology access to ATM network to realize the combination of them. So wireless ATM appears. Wireless ATM is an expansion of ATM network, but wireless communication channel is limit and the frequency of wireless communication channel constantly change at the time of transmission, it brings high error rate, so how to realize quality of service is our attention. The paper just start at here, at first analyzes frame structure, the mechanism of the channel distributing, competition mechanism of the mainly multiple access protocols at present, understands operating mechanism of them, and brings forward the improved idea to the disadvantage of one of them. On the basis of these combines the advantage of other protocols, designs my protocol and has the bold changes to structure of the frame and competition mechanism. Then builds the model of three layers of this protocol through the advanced network simulation software OPNET, discusses about the source model of traffic in theory and carries on the parameter to dispose to this kind of voice traffic in realizing, at last draws the result of the simulation. Through the two traffic model which have different number, comparative simulation situation and analyze the result, explains the advantage and disadvantage of this protocol. At last the paper puts forward some views for wireless ATM technology and has a prospect to this technology.更多还原